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51.
The impact of social defeat on lymphocyte subpopulations and T helper subsets was investigated in Long Evans rats. CD4 T helper cell subsets with distinct functional properties and different cytokine profiles can be distinguished by using the mAbs OX-22 (anti-CD45RC) and OX-7 (anti-CD90, Thy1.1). Male intruders were exposed for 2, 6, or 48 h to aggressive resident pairs. All intruders were attacked upon introduction and were defeated as indicated by frequent display of full submissive postures. After 2 and 48 h of confrontation, drastic but differential effects on blood leukocyte numbers, CD4 and CD8a cells, and CD4 subsets were evident. However, after 6 h of confrontation most lymphocyte subset numbers corresponded to baseline levels. Focusing on CD4 subsets after 2 h of confrontation, we demonstrated that only the number of the CD45RCCD90subset declines, whereas neither the number of the CD45RC+CD90subset nor the number of the CD45RCCD90+subset (recent thymic emigrants) was influenced. Con A stimulation of sorted subsets identified the CD45RCCD90as a poor producer of IFN-γ. The data clearly demonstrate that social factors might differentially influence not only T cell subsets but also T helper cell subsets with distinct cytokine profiles in a possibly time-dependent manner. Such a stress-induced shift toward a CD45RC+CD90-dominated milieu may have important consequences in interpreting results obtained from mitogenic stimulation of blood lymphocytes and cytokine production profiles measured after such a stimulation. In addition, a shift toward a CD45RC+CD90dominance may modify the type and magnitude of immune response, at least temporarily.  相似文献   
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The authors assessed the impact of the Nazi Holocaust on the course and symptoms of posttraumatic stress disorder (PTSD) among Israeli combat stress reaction casualties. They examined a sample of 96 such casualties of the 1982 Lebanon War whose parents had gone through the Nazi Holocaust and compared them to casualties who did not have such family history for 3 consecutive years beginning 1 year after their participation in the war. Results showed that 2 and 3 years after their participation in the 1982 Lebanon War, the children of Holocaust survivors, i.e., "second-generation" casualties, had higher rates of PTSD than did the control subjects, as well as a somewhat different clinical picture. Clinical and methodological implications of the findings are discussed.  相似文献   
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This study describes our experience using a percutaneously placed small-bore catheter for drainage of malignant pleural effusions and subsequent instillation of a sclerosing agent to obliterate the pleural space. We treated 15 consecutive patients with known metastatic cancer and a symptomatic pleural effusion. Twelve patients survived for more than four weeks after the procedure; 11 of these 12 patients had a successful objective clinical response. The procedure was well tolerated, with little or no discomfort during catheter placement and the maintenance period. No serious complications were encountered. We conclude that the use of a small-bore percutaneously placed "pneumothorax" catheter in the management of malignant pleural effusions is an effective and more comfortable alternative to large-bore closed-tube thoracostomy.  相似文献   
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OBJECTIVE: To estimate HIV and sexually transmitted disease (STD) prevalence and behavioral risk characteristics of men who have sex with men (MSM) in Chennai, India. METHODS: A cross-sectional population-based random sample survey was conducted in 2001. Randomly selected residents of 30 slums in Chennai were interviewed for behavioral risk factors through face-to-face interviews. Sera and urine were examined for syphilis, HIV-1, gonorrhea, and chlamydia. Logistic regression analyses were used to assess associations between MSM status and HIV infection and to identify risk characteristics of MSM. RESULTS: Of 774 men, 46 reported (5.9%) sex with other men. MSM were more likely to be seropositive for HIV (odds ratio [OR] = 8.57; 95% confidence interval [CI]: 1.83, 40.23) and were more likely to have a history of STD (OR = 2.66; 95% CI: 1.18, 6.02) than non-MSM. Men who used illicit drugs in past 3 months (adjusted odds ratio [AOR] = 4.01; 95% CI: 1.92, 8.41), ever exchanged money for sex (AOR = 3.93; 95% CI: 1.97, 7.84), or were ever tested for HIV (AOR = 3.72; 95% CI: 1.34, 10.34) were significantly more likely to report sex with men. CONCLUSIONS: MSM in Chennai slums are at high risk for HIV. HIV prevention strategies aimed at changing unsafe drug and sexual practices should target the general population of men, with specific attention to areas with high rates of MSM.  相似文献   
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This paper discusses some consequences of the discovery that antigen receptors are degenerate: Immune specificity, in contrast to the tenets of the clonal selection paradigm, must be generated by the immune response down-stream of initial antigen recognition; and specificity is a property of a collective of cells and not of single clones.  相似文献   
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Cerebrospinal fluid (CSF) was allowed to drop straight into Hanks's balanced salt solution. After centrifugation the pellet was resuspended and mixed with sheep erythrocytes. The mixture was further handled as in the E-rosette test with peripheral blood lymphocytes. CSF from 20 individuals were investigated, and rosette-forming cells (RFC) were found in all. Six patients with normal fluid had between 46% and 83% RFC. Four patients with multiple sclerosis had increased numbers of RFC (94%-96%). Low numbers of RFC were found in one patient with cerebellar ataxia and in one of two patients with acute viral meningitis. With this technique RFC can be counted even in normal CSF with a 3-ml sample.  相似文献   
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The use of laboratory intervention to stem the flow of fresh-frozen plasma   总被引:1,自引:0,他引:1  
Four methods of laboratory intervention were tested by the hospital blood bank in an effort to modify the use of fresh-frozen plasma (FFP). Over a one-year period, a utilization audit was serially initiated with feedback to physicians, a recurrent educational program was introduced for housestaff delineating guidelines for FFP use, a form was introduced requiring justification for FFP orders, and a policy was established requiring pathologist approval of FFP in patients with normal or no coagulation studies. Overall, in comparing the period following all forms of intervention (February 1986-October 1986) to the baseline period prior to any form of intervention (July 1984-March 1985), FFP use dropped 52% in the face of a 17% increase in red blood cell use. It was concluded that blood bankers can dramatically alter the use of this product using established methods for modifying physician ordering behavior.  相似文献   
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